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Digital Filter for Modeling Air Absorption in Real Time

Sound atmospheric attenuation is a relevant aspect of realistic space modeling in 3-D audio simulation systems. A digital filter has been developed on commercial DSP processors to match air absorption curves. This paper focuses on the algorithm implementation of a digital filter with continuous roll-off control, to simulate high frequency damping of audio signals in various atmospheric conditions, along with rules to allow a precise approximation of the behavior described by analytical formulas.